Most junior DBAs write SQL that works. Few write SQL that performs.

After seeing the same patterns come up again and again, here are the three mistakes that slow early-career DBAs down the most:

1. Ignoring execution plans

You write a query, it returns results, you move on. But you never looked at how the database actually executed it. Get comfortable with EXPLAIN / Execution Plans from day one — it'll save you thousands of hours later.

2. Over-indexing everything

Indexes speed up reads but slow down writes. Too many indexes on a table and your INSERT/UPDATE performance tanks. Every index needs a justification.

3. Not thinking in sets

SQL is a set-based language. The moment you reach for a cursor or a row-by-row loop to solve something, ask yourself: can I do this in a single set operation? Almost always, the answer is yes — and it'll run 10x faster.

These aren't advanced concepts. But most people don't learn them until they've already been burned.

That's exactly what The Data Admin newsletter is built to fix — one practical issue at a time, aimed at junior DBAs in their first 3 years.

Welcome — you're in.

Here's what to expect as a member:

📬 Weekly Issues — Every week you'll get a new issue right here covering practical DBA topics: query optimization, index strategy, backup & recovery, performance tuning, and career moves.

💬 Community Chat — Jump into the DBA Community Chat to connect with other junior DBAs, ask questions, and share what you're working on.

Glad you're here. Let's build your DBA career the right way.